The value of regular monitoring and diverse sampling techniques to assess aquatic non-native species: a case study from Orkney Author Kakkonen, Jenni E. * & Marine Services, Harbour Authority Building, Scapa, Orkney, KW 15 1 SD, United Kingdom Author Worsfold, Tim M. APEM Ltd., Diamond Centre, Works Road, Letchworth Garden City, SG 6 1 LW, United Kingdom Author Ashelby, Christopher W. APEM Ltd., Diamond Centre, Works Road, Letchworth Garden City, SG 6 1 LW, United Kingdom Author Taylor, Andrea * & Marine Services, Harbour Authority Building, Scapa, Orkney, KW 15 1 SD, United Kingdom Author Beaton, Katy * & Marine Services, Harbour Authority Building, Scapa, Orkney, KW 15 1 SD, United Kingdom text Management of Biological Invasions 2019 2018-10-17 10 1 46 79 http://dx.doi.org/10.3391/mbi.2019.10.1.04 journal article 299406 10.3391/mbi.2019.10.1.04 a53d05d0-2083-4f05-a83c-8f418fdc5468 1989-8649 11969078 (3) Bonnemaisonia hamifera Hariot, 1891 Status in U.K. – non-native. Bonnemaisonia hamifera (“Bonnemaison’s hook weed”) was introduced to Europe from Japan and was first found in southern England in 1890 ( Maggs and Stegenga 1999 ); it has been recorded from the monitoring programme each year since 2012, at many sites from both rapid assessment and scrape samples. It has previously been recorded from Orkney by Wilkinson (1975) , who found it at Skatelan Skerry, Burray Ness and the Bay of Kirkwall; Nall et al. (2015) summarised other Orkney records from (Marine Nature Conservation Review ( MNCR ) surveys.